Fixed BigNumber/XRegExp incompatibility. CLoses #481

src/core/operations/Divide.mjs

@@ -43,7 +43,7 @@ class Divide extends Operation {
      */
     run(input, args) {
         const val = div(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }

src/core/operations/Mean.mjs

@@ -43,7 +43,7 @@ class Mean extends Operation {
      */
     run(input, args) {
         const val = mean(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }

src/core/operations/Median.mjs

@@ -43,7 +43,7 @@ class Median extends Operation {
      */
     run(input, args) {
         const val = median(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }

src/core/operations/Multiply.mjs

@@ -44,7 +44,7 @@ class Multiply extends Operation {
      */
     run(input, args) {
         const val = multi(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }

src/core/operations/StandardDeviation.mjs

@@ -44,7 +44,7 @@ class StandardDeviation extends Operation {
      */
     run(input, args) {
         const val = stdDev(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
 
     }
 

src/core/operations/Subtract.mjs

@@ -44,7 +44,7 @@ class Subtract extends Operation {
      */
     run(input, args) {
         const val = sub(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }

src/core/operations/Sum.mjs

@@ -44,7 +44,7 @@ class Sum extends Operation {
      */
     run(input, args) {
         const val = sum(createNumArray(input, args[0]));
-        return val instanceof BigNumber ? val : new BigNumber(NaN);
+        return BigNumber.isBigNumber(val) ? val : new BigNumber(NaN);
     }
 
 }